kdump and self compiled kernel

[Christoph Mathys]

I'm trying to get a kernel crashdump from a self-compiled kernel (3.0)
on a 10.04 system. This has been a bit bumpy, but works now with
recent version of kexec-tools, makedumpfile and some hackery on the
script side.

The script 0_kdump expects to find a vmcoreinfo-$KVER. Unfortuanately,
I don't have that file and manual creation failed:
$ makedumpfile -g vmcoreinfo -x
/usr/lib/debug/lib/modules/3.0.17-realtime-1-rt33+/vmlinux
The kernel version is not supported.
The created dumpfile may be incomplete.
generate_vmcoreinfo: Can't find the memory type.

makedumpfile Failed.

Any ideas why I can't create vmcoreinfo from the kernels debug symbols?


Apparently, recent kernels already contain vmcoreinfo in /proc/vmcore.
[0] So I went ahead and changed the invocation of makedumpfile in
'0_kdump' to not pass a reference to the info file (I removed "-i
$INFO"). This gives me a kernel core dump as expected which I can
analyse with 'crash' and the debug symbols for my kernel.
Could 0_kdump be changed to try -i, -x, and then fall back to not pass
any of the two?


When the system reboots, apport/kernel_crashdump is run, which deletes
the core file and leaves behind .crash file. How can I work with this
file? What information does it contain?

[0] http://lists.infradead.org/pipermail/kexec/2007-August/000521.html

Christoph